Answer:
Before we graph 
we know that the slope, mx, could be read as 
. To graph the the equation of the line, we begin at the point (0,0). From that point, because our rise is negative (-1), instead of moving upwards or vertically, we will move downards. Therefore, from point 0, we will vertically move downwards one time. Now, our point is on point -1 on the y-axis. Now, we have 2 as our run. From point -1, we move to the right two times. We land on point (2,-1). Because we need various points to graph this equation, we must continue on. In the end, the graph will look like the first graph given.
For the equation y = 2, the line will be plainly horizontal. Why? Because x has no value in the equation. The variable 
does not exist in this linear equation. Therefore, it will look like the second graph below. We graph this by plotting the point, (0,2), on the y-axis.
The difference between them is 10
-4 - 6 = -10, however since it is only asking for the <em>difference, </em>your answer would be 10.
A constant is a number that never changes value. Example:
x + 3 = 5, 3 and 5 are constants.
A)= 2/20 or 1/10
B)=16/20 or 4/5
C)=1/5
Sorry, I guess I was in a hurry. This is how I did it after carefully reading the problem.
9.54% times which mobile phone (the one we are looking for=y) would use 1.908
that is: 0.0954 times y=1.908
0.0954y=1.908 dividing each side by 0.0954, we get y=20
So, the answer is y=20, or the mobile phone is 20
